X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=mm%2Fmigrate.c;h=b10237d8b459823b84f1b2a070a823532d585d34;hb=894bc310419ac95f4fa4142dc364401a7e607f65;hp=2a80136b23bbc16fb9d2ec2fad932b29e30dda50;hpb=accba5f3965d6a9d1bf7c1e1a7995d17e9d521b6;p=linux-2.6-omap-h63xx.git

diff --git a/mm/migrate.c b/mm/migrate.c
index 2a80136b23b..b10237d8b45 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -36,36 +36,6 @@
 
 #define lru_to_page(_head) (list_entry((_head)->prev, struct page, lru))
 
-/*
- * Isolate one page from the LRU lists. If successful put it onto
- * the indicated list with elevated page count.
- *
- * Result:
- *  -EBUSY: page not on LRU list
- *  0: page removed from LRU list and added to the specified list.
- */
-int isolate_lru_page(struct page *page, struct list_head *pagelist)
-{
-	int ret = -EBUSY;
-
-	if (PageLRU(page)) {
-		struct zone *zone = page_zone(page);
-
-		spin_lock_irq(&zone->lru_lock);
-		if (PageLRU(page) && get_page_unless_zero(page)) {
-			ret = 0;
-			ClearPageLRU(page);
-			if (PageActive(page))
-				del_page_from_active_list(zone, page);
-			else
-				del_page_from_inactive_list(zone, page);
-			list_add_tail(&page->lru, pagelist);
-		}
-		spin_unlock_irq(&zone->lru_lock);
-	}
-	return ret;
-}
-
 /*
  * migrate_prep() needs to be called before we start compiling a list of pages
  * to be migrated using isolate_lru_page().
@@ -83,23 +53,9 @@ int migrate_prep(void)
 	return 0;
 }
 
-static inline void move_to_lru(struct page *page)
-{
-	if (PageActive(page)) {
-		/*
-		 * lru_cache_add_active checks that
-		 * the PG_active bit is off.
-		 */
-		ClearPageActive(page);
-		lru_cache_add_active(page);
-	} else {
-		lru_cache_add(page);
-	}
-	put_page(page);
-}
-
 /*
- * Add isolated pages on the list back to the LRU.
+ * Add isolated pages on the list back to the LRU under page lock
+ * to avoid leaking evictable pages back onto unevictable list.
  *
  * returns the number of pages put back.
  */
@@ -111,7 +67,7 @@ int putback_lru_pages(struct list_head *l)
 
 	list_for_each_entry_safe(page, page2, l, lru) {
 		list_del(&page->lru);
-		move_to_lru(page);
+		putback_lru_page(page);
 		count++;
 	}
 	return count;
@@ -393,8 +349,11 @@ static void migrate_page_copy(struct page *newpage, struct page *page)
 		SetPageReferenced(newpage);
 	if (PageUptodate(page))
 		SetPageUptodate(newpage);
-	if (PageActive(page))
+	if (TestClearPageActive(page)) {
+		VM_BUG_ON(PageUnevictable(page));
 		SetPageActive(newpage);
+	} else
+		unevictable_migrate_page(newpage, page);
 	if (PageChecked(page))
 		SetPageChecked(newpage);
 	if (PageMappedToDisk(page))
@@ -415,7 +374,6 @@ static void migrate_page_copy(struct page *newpage, struct page *page)
 #ifdef CONFIG_SWAP
 	ClearPageSwapCache(page);
 #endif
-	ClearPageActive(page);
 	ClearPagePrivate(page);
 	set_page_private(page, 0);
 	page->mapping = NULL;
@@ -594,6 +552,10 @@ static int fallback_migrate_page(struct address_space *mapping,
  *
  * The new page will have replaced the old page if this function
  * is successful.
+ *
+ * Return value:
+ *   < 0 - error code
+ *  == 0 - success
  */
 static int move_to_new_page(struct page *newpage, struct page *page)
 {
@@ -611,6 +573,8 @@ static int move_to_new_page(struct page *newpage, struct page *page)
 	/* Prepare mapping for the new page.*/
 	newpage->index = page->index;
 	newpage->mapping = page->mapping;
+	if (PageSwapBacked(page))
+		SetPageSwapBacked(newpage);
 
 	mapping = page_mapping(page);
 	if (!mapping)
@@ -654,9 +618,10 @@ static int unmap_and_move(new_page_t get_new_page, unsigned long private,
 	if (!newpage)
 		return -ENOMEM;
 
-	if (page_count(page) == 1)
+	if (page_count(page) == 1) {
 		/* page was freed from under us. So we are done. */
 		goto move_newpage;
+	}
 
 	charge = mem_cgroup_prepare_migration(page, newpage);
 	if (charge == -ENOMEM) {
@@ -730,7 +695,6 @@ rcu_unlock:
 		rcu_read_unlock();
 
 unlock:
-
 	unlock_page(page);
 
 	if (rc != -EAGAIN) {
@@ -741,17 +705,19 @@ unlock:
  		 * restored.
  		 */
  		list_del(&page->lru);
- 		move_to_lru(page);
+		putback_lru_page(page);
 	}
 
 move_newpage:
 	if (!charge)
 		mem_cgroup_end_migration(newpage);
+
 	/*
 	 * Move the new page to the LRU. If migration was not successful
 	 * then this will free the page.
 	 */
-	move_to_lru(newpage);
+	putback_lru_page(newpage);
+
 	if (result) {
 		if (rc)
 			*result = rc;
@@ -914,7 +880,9 @@ static int do_move_pages(struct mm_struct *mm, struct page_to_node *pm,
 				!migrate_all)
 			goto put_and_set;
 
-		err = isolate_lru_page(page, &pagelist);
+		err = isolate_lru_page(page);
+		if (!err)
+			list_add_tail(&page->lru, &pagelist);
 put_and_set:
 		/*
 		 * Either remove the duplicate refcount from